Maui REST API

What it does

When your agent uses it

• JSON deserialization
• CRUD operations
• Clear-text traffic
• Consume API MAUI

Example prompts

• “REST API”
• “HttpClient”
• “call API”
• “/maui-rest-api”

Workflow steps

5 steps, taken from the step headings in SKILL.md.

1. 1Creating HttpClient per request
2. 2Blocking with .Result or .Wait()
3. 3Deserializing before checking status
4. 4Hardcoding BaseAddress in service methods
5. 5Missing error handling for network failures

What it can do on your machine

Read from SKILL.md and the folder at commit 79bb4bf. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are csharp).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Maui REST API loads about 1.2k tokens when it runs, and up to ~2.5k if it reads all its reference files. Until then it costs about 167 tokens; SKILL.md has 223 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~167

When it runs · the whole SKILL.md, loaded when a task matches

~1.2k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~2.5k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from davidortinau/maui-skills at commit 79bb4bf, republished under its MIT licence (© davidortinau). 223 words, ~1,224 tokens.

name

maui-rest-api

description

Guidance for consuming REST APIs in .NET MAUI apps. Covers HttpClient setup with System.Text.Json, DI registration, service interface/implementation pattern, full CRUD operations (GET, POST, PUT, DELETE), error handling, platform-specific clear-text traffic configuration, and async/await best practices. USE FOR: "REST API", "HttpClient", "call API", "GET request", "POST request", "API service", "JSON deserialization", "CRUD operations", "clear-text traffic", "consume API MAUI". DO NOT USE FOR: Aspire service discovery (use maui-aspire), authentication token handling (use maui-authentication), or local database storage (use maui-sqlite-database).

// ❌ Creates socket exhaustion — each instance opens a new connection
public async Task<List<Item>> GetItemsAsync()
{
    using var client = new HttpClient();
    var response = await client.GetAsync("https://api.example.com/items");
    // ...
}

// ✅ Register once in DI, inject everywhere
builder.Services.AddSingleton(sp => new HttpClient
{
    BaseAddress = new Uri("https://api.example.com")
});

// ❌ Deadlocks on the UI thread
var items = _apiService.GetItemsAsync().Result;

// ✅ Always use async/await
var items = await _apiService.GetItemsAsync();

// ❌ Tries to deserialize error HTML/JSON as your model
var content = await response.Content.ReadAsStringAsync();
var items = JsonSerializer.Deserialize<List<Item>>(content, _jsonOptions);

// ✅ Check status first
response.EnsureSuccessStatusCode();
var content = await response.Content.ReadAsStringAsync();
var items = JsonSerializer.Deserialize<List<Item>>(content, _jsonOptions) ?? [];

// ❌ Absolute URIs in every method — hard to change, easy to typo
await _httpClient.GetAsync("https://api.example.com/api/items");

// ✅ Set BaseAddress in DI, use relative URIs in methods
await _httpClient.GetAsync("api/items");

// ❌ Crashes on network timeout, DNS failure, etc.
var items = await _apiService.GetItemsAsync();

// ✅ Catch both network and deserialization errors
try
{
    var items = await _apiService.GetItemsAsync();
}
catch (HttpRequestException ex) { /* network or HTTP error */ }
catch (JsonException ex) { /* malformed response */ }

// ❌ On Android emulator, this hits the emulator, not your dev machine
new Uri("http://localhost:5000")

// ✅ Use the emulator's host loopback address
new Uri("http://10.0.2.2:5000")

// ❌ Properties stay null/default — no error thrown
JsonSerializer.Deserialize<Item>(content);

// ✅ Configure casing policy
private static readonly JsonSerializerOptions _jsonOptions = new()
{
    PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
    PropertyNameCaseInsensitive = true
};

© davidortinau, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 1 other file (references) in plugins/maui-skills/skills/maui-rest-api of davidortinau/maui-skills.

• SKILL.md
• references/rest-api-reference.md

Open the folder on GitHubat commit 79bb4bf